The present invention relates to a magnetic resonance apparatus for performing a sequence for acquiring an echo train from a subject, and a program applied to the magnetic resonance apparatus.
In imaging a subject with a magnetic resonance apparatus, an operator is required to set a scan condition. In setting the scan condition, however, the operator must specify values for a wide variety of parameters, which poses a problem that the operator experiences much stress. Moreover, there is another problem that the operator may sometimes specify values leading to a lengthened scan time and/or deteriorated image quality.
A fast spin echo (FSE) technique has been known as an imaging method using a magnetic resonance apparatus. The FSE technique is a method suitable for reducing the scan time because it enables a plurality of echoes to be acquired by one excitation. In setting a scan condition in the FSE technique, the operator inputs values for several kinds of parameters (resolution, echo train length, etc.). Once these parameter values have been input, a scan time is calculated based on the parameter values specified by the operator. The scan time is displayed in a display section. The operator observes the scan time displayed in the display section, and in the case that the scan time is too long, he/she modifies a value of the echo train length. As soon as the value of the echo train length has been modified, a scan time is recalculated based on the modified value of the echo train length, and the recalculated scan time is displayed in the display section. The operator observes the scan time newly displayed in the display section. Similarly, thereafter, the operator modifies the echo train length while observing how the scan time varies with the value of the echo train length, and determines a final value of the echo train length.
On the other hand, the echo train length affects image quality, so that it is desirable to define the echo train length that gives good image quality. However, it is not easy for an operator to recognize how image quality varies with the echo train length. Here arises a problem that it is difficult for an operator to specify the echo train length that gives an image with good image quality.
Accordingly, it would be desirable to provide a technique capable of automatically obtaining an optimal value for the echo train length.